﻿#region File and License Information
/*
<File>
	<License Type="BSD">
		Copyright © 2009 - 2012, Outcoder. All rights reserved.
	
		This file is part of Calcium (http://calciumsdk.net).

		Redistribution and use in source and binary forms, with or without
		modification, are permitted provided that the following conditions are met:
			* Redistributions of source code must retain the above copyright
			  notice, this list of conditions and the following disclaimer.
			* Redistributions in binary form must reproduce the above copyright
			  notice, this list of conditions and the following disclaimer in the
			  documentation and/or other materials provided with the distribution.
			* Neither the name of the <organization> nor the
			  names of its contributors may be used to endorse or promote products
			  derived from this software without specific prior written permission.

		THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
		ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
		DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
		(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
		LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
		ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
		(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
		SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	</License>
	<Owner Name="Daniel Vaughan" Email="danielvaughan@outcoder.com" />
	<CreationDate>2010-11-20 13:28:27Z</CreationDate>
</File>
*/
#endregion

using System;
using System.Collections;
using System.Collections.Specialized;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Markup;
using System.Windows.Media;

using Outcoder.Collections;
using Outcoder.UI.Xaml.Controls.Design;

using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;

namespace Outcoder.UI.Xaml.Controls
{
    [ContentProperty("Buttons")]
    public class AppBar : ItemsControl, IApplicationBar
    {
        readonly ApplicationBar applicationBar = new ApplicationBar();
        bool loaded;

        public AppBar()
        {
            Loaded += HandleLoaded;
	        Unloaded += HandleUnloaded;
		}

	    void HandleLoaded(object sender, RoutedEventArgs e)
        {
            if (loaded)
            {
                return;
            }

            if (AutoAttach)
            {
                Attach();
            }

            loaded = true;
        }

        public void Attach()
        {
            var page = this.GetVisualAncestors<PhoneApplicationPage>()
                                                .FirstOrDefault();

	        bool inPivotOrPano = false;
            var pivot = this.GetVisualAncestors<Pivot>().FirstOrDefault();
            if (pivot != null)
            {
	            inPivotOrPano = true;

                pivot.SelectionChanged -= pivot_SelectionChanged;
                pivot.SelectionChanged += pivot_SelectionChanged;
                UpdateApplicationBar(pivot);
            }
            else
            {
	            var panorama = this.GetVisualAncestors<Panorama>().FirstOrDefault();
	            if (panorama != null)
	            {
		            inPivotOrPano = true;

		            panorama.SelectionChanged -= panorama_SelectionChanged;
		            panorama.SelectionChanged += panorama_SelectionChanged;
	            }
            }

			if (!inPivotOrPano && page != null)
            {
                page.ApplicationBar = applicationBar;
                Build();
            }

			SubscribeToApplicationBarEvents(applicationBar);

			PhoneApplicationService.Current.Deactivated -= HandleAppDeactivated;
			PhoneApplicationService.Current.Deactivated += HandleAppDeactivated;
        }

	    void HandleAppDeactivated(object sender, DeactivatedEventArgs e)
	    {
		    IsMenuVisible = false;
	    }

	    void HandleUnloaded(object sender, RoutedEventArgs e)
		{
			Detach();

			loaded = false;
		}

		void Detach()
		{
			var pivot = this.GetVisualAncestors<Pivot>().FirstOrDefault();
			if (pivot != null)
			{
				pivot.SelectionChanged -= pivot_SelectionChanged;
			}

			var panorama = this.GetVisualAncestors<Panorama>().FirstOrDefault();
			if (panorama != null)
			{
				panorama.SelectionChanged -= panorama_SelectionChanged;
			}

			UnsubscribeToApplicationBarEvents(applicationBar);

			applicationBar.Buttons.Clear();
			applicationBar.MenuItems.Clear();

			foreach (FrameworkElement item in Items.OfType<FrameworkElement>())
			{
				UnregisterForVisibilityNotification(item);
			}

			PhoneApplicationService.Current.Deactivated -= HandleAppDeactivated;
		}

	    void SubscribeToApplicationBarEvents(ApplicationBar bar)
	    {
		    UnsubscribeToApplicationBarEvents(bar);
			bar.StateChanged += HandleApplicationBarStateChanged;
	    }

		void UnsubscribeToApplicationBarEvents(ApplicationBar bar)
		{
			bar.StateChanged -= HandleApplicationBarStateChanged;
		}

	    void HandleApplicationBarStateChanged(object sender, ApplicationBarStateChangedEventArgs args)
	    {
		    bool newValue = args.IsMenuVisible;
		    bool currentValue = IsMenuVisible;

			if (currentValue != newValue)
			{
				IsMenuVisible = newValue;
			}

			StateChanged?.Invoke(this, args);
	    }

	    void pivot_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            UpdateApplicationBar((Pivot)sender);
        }

		void panorama_SelectionChanged(object sender, SelectionChangedEventArgs e)
		{
			UpdateApplicationBar((Panorama)sender);
		}

        protected virtual void UpdateApplicationBar(Pivot pivot)
        {
            var page = this.GetVisualAncestors<PhoneApplicationPage>().LastOrDefault();

            if (pivot == null || page == null)
            {
                return;
            }

            bool assignBar = false;

            if (pivot.SelectedItem == DataContext)
            {
                assignBar = true;
            }
            else
            {
                var frameworkElement = pivot.SelectedItem as FrameworkElement;
                if (frameworkElement != null
                        && frameworkElement.DataContext == DataContext)
                {
                    assignBar = true;
                }
            }

            if (assignBar)
            {
                page.ApplicationBar = applicationBar;
                Build();
            }
            else if (page.ApplicationBar == applicationBar)
            {
                page.ApplicationBar = null;
            }
        }

	    protected virtual void UpdateApplicationBar(Panorama panorama)
	    {
			var page = this.GetVisualAncestors<PhoneApplicationPage>().LastOrDefault();

			if (panorama == null || page == null)
			{
				return;
			}

			bool assignBar = false;

			if (panorama.SelectedItem == DataContext)
			{
				assignBar = true;
			}
			else
			{
				var panoramaItem = panorama.SelectedItem as PanoramaItem;
				if (panoramaItem != null)
				{
					var childElement = panoramaItem.Content as FrameworkElement;
					if (childElement != null && childElement.DataContext == DataContext)
					{
						assignBar = true;
					}
				}

				if (!assignBar)
				{
					var frameworkElement = panorama.SelectedItem as FrameworkElement;
					if (frameworkElement != null
					    && frameworkElement.DataContext == DataContext)
					{
						assignBar = true;
					}
				}
			}

			if (assignBar)
			{
				page.ApplicationBar = applicationBar;
				Build();
			}
			else if (page.ApplicationBar == applicationBar)
			{
				page.ApplicationBar = null;
			}
	    }

	    #region AutoAttach

        public static DependencyProperty AutoAttachProperty
            = DependencyProperty.Register(
                "AutoAttach",
                typeof(bool),
                typeof(AppBar),
                new PropertyMetadata(true));

        public bool AutoAttach
        {
            get
            {
                return (bool)GetValue(AutoAttachProperty);
            }
            set
            {
                SetValue(AutoAttachProperty, value);
            }
        }

        #endregion

        protected override void OnItemsChanged(NotifyCollectionChangedEventArgs e)
        {
            base.OnItemsChanged(e);
            if (loaded)
            {
                Build();
            }
        }

        bool building;

        void Build()
        {
            if (building)
            {
                return;
            }

            try
            {
                building = true;
                BuildAux();
            }
            finally
            {
                building = false;
            }
        }

        void BuildAux()
        {
            applicationBar.Buttons.Clear();
            applicationBar.MenuItems.Clear();

            foreach (FrameworkElement item in Items.OfType<FrameworkElement>())
            {
                RegisterVisibilityNotification("Visibility", item);
            }

	        const int maxButtons = 4;
	        int buttonCount = 0;

	        foreach (object item in Items)
	        {
		        var uiElement = item as UIElement;
				if (uiElement != null && uiElement.Visibility != Visibility.Visible)
				{
					continue;
				}

		        IApplicationBarIconButtonProvider buttonProvider 
					= item as IApplicationBarIconButtonProvider;
				if (buttonProvider != null && ++buttonCount <= maxButtons)
				{
					applicationBar.Buttons.Add(buttonProvider.Button);
				}

		        var menuItemProvider = item as IApplicationBarMenuItemProvider;

				if (menuItemProvider != null)
				{
					applicationBar.MenuItems.Add(menuItemProvider.MenuItem);
				}
	        }

			//var buttonList = (from button in Items.Where(notUIElementOrVisibleFunc)
			//                            .OfType<IApplicationBarIconButtonProvider>()
			//                    select button.Button).ToList();
			//
			//if (buttonList.Count > 4)
			//{
			//    buttonList = buttonList.Take(4).ToList();
			//}

            //applicationBar.Buttons.AddRange(buttonList);

			//var menuItemList = (from item
			//                        in Items.Where(notUIElementOrVisibleFunc)
			//                            .OfType<IApplicationBarMenuItemProvider>()
			//                    select item.MenuItem).ToList();
			//
			//applicationBar.MenuItems.AddRange(menuItemList);
        }

        readonly Func<object, bool> notUIElementOrVisibleFunc
            = x =>
            {
                var element = x as UIElement;
                return element == null || element.Visibility == Visibility.Visible;
            };

        #region ItemVisibility

		readonly static DependencyProperty ItemVisibilityProperty 
			= DependencyProperty.RegisterAttached(
				"ItemVisibility",
				typeof(Visibility),
				typeof(UserControl),
				new PropertyMetadata(HandleItemVisibilityChanged));

	    static void HandleItemVisibilityChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
	    {
		    FrameworkElement element = (FrameworkElement)d;
			AppBar appBar = element.FindAncestor<AppBar>();
			if (appBar == null)
			{
				return;
			}

			if (appBar.loaded)
            {
				appBar.Build();
            }
        }

        public Visibility ItemVisibility
        {
            get
            {
                return (Visibility)GetValue(ItemVisibilityProperty);
            }
            set
            {
                SetValue(ItemVisibilityProperty, value);
            }
        }

        #endregion

        void RegisterVisibilityNotification(
							string propertyName,
							FrameworkElement element)
        {
            var expression = element.GetBindingExpression(ItemVisibilityProperty);
            if (expression == null)
            {
                Binding binding = new Binding(propertyName) { Source = element };
                element.SetBinding(ItemVisibilityProperty, binding);
            }
        }

		void UnregisterForVisibilityNotification(FrameworkElement element)
		{
			var expression = element.GetBindingExpression(ItemVisibilityProperty);
			if (expression != null)
			{
				element.ClearValue(ItemVisibilityProperty);
				//element.SetBinding(ItemVisibilityProperty, null);
			}
		}

        //		static void RegisterForNotification(
        //			string propertyName,
        //			FrameworkElement element,
        //			PropertyChangedCallback callback)
        //		{
        //			Binding binding = new Binding(propertyName) { Source = element };
        //			var property = DependencyProperty.RegisterAttached(
        //								"ChangeListenerAttached" + propertyName,
        //								typeof(object),
        //								typeof(UserControl),
        //								new PropertyMetadata(callback));
        //
        //			element.SetBinding(property, binding);
        //		}

        //		void OnItemVisibilityChanged(
        //			DependencyObject d, DependencyPropertyChangedEventArgs e)
        //		{
        //			if (loaded)
        //			{
        //				Build();
        //			}
        //		}

        public IList Buttons
        {
            get
            {
                return Items;
            }
        }

        public IList MenuItems
        {
            get
            {
                return Items;
            }
        }

		public event EventHandler<ApplicationBarStateChangedEventArgs> StateChanged = delegate { };
		
        #region IsMenuEnabled

        public static readonly DependencyProperty IsMenuEnabledProperty
            = DependencyProperty.RegisterAttached(
                "IsMenuEnabled",
                typeof(bool),
                typeof(AppBar),
                new PropertyMetadata(true, HandleMenuEnabledChanged));

        static void HandleMenuEnabledChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            AppBar bar;
            if (e.NewValue != e.OldValue && (bar = d as AppBar) != null)
            {
                bar.applicationBar.IsMenuEnabled = (bool)e.NewValue;
            }
        }

        public bool IsMenuEnabled
        {
            get
            {
                return (bool)GetValue(IsMenuEnabledProperty);
            }
            set
            {
                SetValue(IsMenuEnabledProperty, value);
            }
        }

        #endregion

		#region IsMenuVisible

		public static readonly DependencyProperty IsMenuVisibleProperty
			= DependencyProperty.RegisterAttached(
				"IsMenuVisible",
				typeof(bool),
				typeof(AppBar),
				new PropertyMetadata(true, HandleMenuVisibleChanged));

		static void HandleMenuVisibleChanged(
			DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			AppBar bar;
			if (e.NewValue != e.OldValue && (bar = d as AppBar) != null)
			{
				//bar.applicationBar.IsMenuVisible = (bool)e.NewValue;
			}
		}

		public bool IsMenuVisible
		{
			get
			{
				return (bool)GetValue(IsMenuVisibleProperty);
			}
			set
			{
				SetValue(IsMenuVisibleProperty, value);
			}
		}

		#endregion

        #region IsVisible

        public static readonly DependencyProperty IsVisibleProperty
            = DependencyProperty.RegisterAttached(
                "IsVisible",
                typeof(bool),
                typeof(AppBar),
                new PropertyMetadata(true, HandleIsVisibleChanged));

        static void HandleIsVisibleChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            AppBar bar;
            if (e.NewValue != e.OldValue
                && (bar = d as AppBar) != null)
            {
                bar.applicationBar.IsVisible = (bool)e.NewValue;
            }
        }

        public bool IsVisible
        {
            get
            {
                return (bool)GetValue(IsVisibleProperty);
            }
            set
            {
                SetValue(IsVisibleProperty, value);
            }
        }

        #endregion

        #region BarOpacity

        public static DependencyProperty BarOpacityProperty
            = DependencyProperty.Register(
                "BarOpacity",
                typeof(double),
                typeof(AppBar),
                new PropertyMetadata(1.0, HandleBarOpacityChanged));

        static void HandleBarOpacityChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var appBar = (AppBar)d;
            appBar.applicationBar.Opacity = (double)e.NewValue;
        }

        public double BarOpacity
        {
            get
            {
                return (double)GetValue(BarOpacityProperty);
            }
            set
            {
                SetValue(BarOpacityProperty, value);
            }
        }

        #endregion

        #region BackgroundColor

        public static DependencyProperty BackgroundColorProperty
            = DependencyProperty.Register(
                "BackgroundColor",
                typeof(Color),
                typeof(AppBar),
                new PropertyMetadata(HandleBackgroundColorChanged));

        static void HandleBackgroundColorChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var appBar = (AppBar)d;
	        if (appBar.applicationBar != null)
	        {
		        appBar.applicationBar.BackgroundColor = (Color)e.NewValue;
	        }
	        else
	        {
				/* If the applicationBar is null, then wait for initialization. */
		        Deployment.Current.Dispatcher.BeginInvoke(delegate
		        {
					if (appBar.applicationBar != null)
					{
						appBar.applicationBar.BackgroundColor = (Color)e.NewValue;
					}
		        });
	        }
        }

        public Color BackgroundColor
        {
            get
            {
                return (Color)GetValue(BackgroundColorProperty);
            }
            set
            {
                SetValue(BackgroundColorProperty, value);
            }
        }

        #endregion

        #region ForegroundColor

        public static DependencyProperty ForegroundColorProperty
            = DependencyProperty.Register(
                "ForegroundColor",
                typeof(Color),
                typeof(AppBar),
                new PropertyMetadata(HandleForegroundColorChanged));

        static void HandleForegroundColorChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var appBar = (AppBar)d;
            appBar.applicationBar.ForegroundColor = (Color)e.NewValue;
        }

        public Color ForegroundColor
        {
            get
            {
                return (Color)GetValue(ForegroundColorProperty);
            }
            set
            {
                SetValue(ForegroundColorProperty, value);
            }
        }

        #endregion

        #region Mode

        public static DependencyProperty ModeProperty
            = DependencyProperty.Register(
                "Mode",
                typeof(ApplicationBarMode),
                typeof(AppBar),
                new PropertyMetadata(ApplicationBarMode.Default, HandleModeChanged));

        static void HandleModeChanged(
            DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var appBar = (AppBar)d;
            appBar.applicationBar.Mode = (ApplicationBarMode)e.NewValue;
        }

        public ApplicationBarMode Mode
        {
            get
            {
                return (ApplicationBarMode)GetValue(ModeProperty);
            }
            set
            {
                SetValue(ModeProperty, value);
            }
        }

        #endregion

        public double DefaultSize
        {
            get
            {
                return applicationBar != null ? applicationBar.DefaultSize : 72.0;
            }
        }

        public double MiniSize
        {
            get
            {
                return applicationBar != null ? applicationBar.MiniSize : 30.0;
            }
        }
    }
}
